Teva UK Ltd v Merck & Co, Inc [2009] EWHC 2952 (Pat)

This article was first published in the February 2010 edition of the World Intellectual Property Report.

Hurdling the expectation of success barrier

In a Judgment handed down by Floyd J on Friday 20 November 2009, Teva managed to succeed in invalidating at first instance a patent owned by Merck concerning a co-formulation of two actives (timolol and dorzolamide) for the treatment of glaucoma on the basis of obviousness.

In his Judgment, Floyd J reviewed the law of obviousness in light of the House of Lords Judgment in Conor v Angiotech. He then went on to apply the law to the facts in the case which were somewhat unusual in that the only clinical example of the use of the combination in the patent in suit was effectively the same as the single piece of prior art being cited in support of the obviousness case. The cited prior art was in fact an abstract of a paper to be presented at a conference after the priority date of the patent but published in the conference papers shortly before the priority date. In both cases, the use was of co-administration of the two actives rather than administration of a co-formulation of the two actives.

Although the abstract referred to one of the two actives (dorzolamide) by reference to an internal code (NK-507), the Judge held that there was no invention in ascertaining the identity (i.e., chemical formula) of that active at the relevant time.

Floyd J concluded first that on the basis of his detailed findings on the state of the common general knowledge, the information contained in the abstract would have made it “startlingly” obvious to the skilled team at the relevant time to have considered co-formulating the two actives and further that it would have been obvious for the skilled team to have proceeded to co-formulate the two actives and then to have tested the co-formulation pre-clinically on animals and then clinically on humans. He dismissed various arguments raised by the patentee as to the difficulties which would have been faced by the skilled team in both co-formulating the two actives and also carrying out the pre-clinical and clinical trials.

He held that had the patent not been invalid for obviousness, it would regardless have been invalid for insufficiency on the basis that the patent contained no more information about the co-formulation than the abstract had done.

The Judge also held that an amendment to an independent process claim so as to narrow the pH range of the co-formulation was not permitted because it added matter to the application. In any event, he held that the finding of obviousness applied to the amended claim as well as the unamended claim, it being obvious to co-formulate the two actives at a pH within both the wider and the narrower pH ranges.

As the Judge noted at paragraph 98 of his judgment: “One must proceed with caution when faced with an obviousness attack based on a suggestion that the skilled person would embark on a research program in the course of which he would discover that a product or compound was effective. This is particularly so where the technical effect is one which is newly discovered, or impossible or very hard to predict. That is because the expectation of success may be zero, or inadequate to drive the research forward. In the end it will all depend on weighing the various factors as they appear from the evidence in the case”.

On the basis of the particular piece of cited prior art coupled with the evidence adduced by the parties through their experts at the trial, it was held that the expectation of being able to successfully co-formulate the two actives and test the resulting co-formulation pre-clinically and clinically was sufficiently high to lead to a finding of obviousness. The judgment demonstrates however how difficult this task remains in most cases.

At the hearing on the Order on the Judgment, Floyd J refused to grant Merck permission to appeal to the Court of Appeal. Merck indicated that they would apply to the Court of Appeal for permission. It remains to be seen whether if they do so, their application will be successful.